Search The Blog

Follow me on Twitter

Q: We’ve had a pretty hard winter. What can I expect when the ice finally melts?

Kevin – Downers Grove, IL

A: Yep, this has indeed been a long, cold winter for much of the country. We’ve shivered through frigid temperatures, shoveled and slogged through snow banks, and watched our ponds and lakes freeze over.

Unfortunately, that could mean trouble for your fish.

When the ice on your pond finally melts this spring, you might discover that your fish and other aquatic life haven’t survived the season. These winter fish kills occur when the ice prevents gas exchange and reduces the amount of dissolved oxygen in the water.

“Winterkill begins with distressed fish gasping for air at holes in the ice and often ends with large numbers of dead fish that bloat as the water warms in early spring,” he explains. “Dead fish and other aquatic life may appear fuzzy because of secondary infection by fungus, but the fungus was not the cause of death. The fish actually suffocated from a lack of dissolved oxygen from decaying plants and other dead aquatic animals under the ice.”

You can’t bring your fish back to life, but you can prevent winterkill from happening in the future by aerating your pond year-round with an Airmax® Pond Series™ Aeration System. Here’s how it works:

It reduces the amount of decomposing debris in the pond, encouraging the colonization of beneficial aerobic bacteria, which prevents muck and nutrient accumulation and maintains clear water.

It keeps an air hole open in the ice, allowing harmful gases to escape while delivering fresh oxygen to your fish.

It pumps even more fresh oxygen into the water via diffusers that sit on the bottom of the pond.

A little pond preparation can go a long way, especially when it comes to unknown variables like weather. Let’s hope next winter is milder than this one was!

Pond Talk: Have you experienced a winterkill in your pond or lake before?

6 Responses

I’m so glad I added one of your PondAir Aeration systems(4) and two deicers to my pond this year. Today, I started to remove the leaf debris from the bottom of our ponds. We do not have fish , but we do have Frogs and Tadpoles. What I found so far is that they are alive and doing fine. Now last year it was a different story, In late Feb. 2013, we removed more than 14 dead frogs and many dead tadpoles .That broke my heart. I believe the Aeration and deicers did their job, even in this horrible frigid winter we had this year .I would recommend everyone add these items next fall.

I, too, lost my fish from this past winter in Northern Michigan, the first time in 7 years.I had kept a hole open with a heater and thought that would help take care off the problem. My pond is about 800 gallons. Is there an aeration system for a pond of that size? I am hoping I won’t have to invest in an aeration system as costly as the one mentioned in your email. I would appreciate your recommendation for me. Thank you!

Hi Jo – The aeration systems in this article are recommend for large ponds and lakes (in terms of acres). For your 800 gallon pond, we recommend using the PondAir™2. Aeration units can be used in conjunction with de-icers to keep an open area in your pond. Here is an article that explains Water Garden Aeration and De-Icers: Do I need a heater to overwinter my fish in the pond?

All of our fish, sadly, have died. This was a first for us in 14 years of having the pond in our backyard. We live in Du Page County. Wish we would have known to jeep the deep snow off of the ice. Plus having the pond heater fail for a day or 2 did not help!